The trial court erred by allowing the State, at the beginning of trial, to amend the indictment charging the defendant with trafficking in heroin to allege trafficking in opiates. In connection with a drug investigation, an officer and informant waited in a hotel room for the defendant. The defendant arrived in a vehicle and, carrying a child in his arms, approached the room. Events ensued and the defendant admitted having placed a packet of heroin in the child’s pants. The defendant was arrested and the car was searched. A search of the car produced: two digital scales; a partially smoked marijuana “blunt;” $800 in cash; a key box under the hood containing balloons of heroin, a pill bottle containing marijuana, crack cocaine and 17 hydrocodone pills; and a revolver wrapped in a sock. The hydrocodone weighed 4.62 grams; the heroin recovered from the child’s pants weighed .84 grams; and the heroin found in the car weighed 3.77 grams. The minimum amount for trafficking in heroin is 4 grams; thus, the only way for the State to prove that minimum was to prove that the defendant possessed both the heroin found in the car and the smaller quality of heroin found in the child’s pants. At a pretrial hearing, the State dismissed several charges leaving the following charges in place: possession of a firearm by a felon, possession of marijuana, possession with intent to sell or deliver cocaine, trafficking in heroin by transportation, and trafficking in heroin by possession. At this point, defense counsel informed the court that the defendant would admit to the heroin found in the child’s pants. The prosecutor then asked to amend the trafficking indictments from trafficking in heroin to trafficking in opiates. The trial court granted the State’s motion to amend, over the defendant’s objection. The defendant was convicted on the trafficking charges. The court noted that here, the amendment broadened the scope of the original indictment to allege trafficking in “opiates,” a category of controlled substances, rather than “heroin,” a specific controlled substance. It did so, the court reasoned, for the purpose of bringing an additional controlled substance—hydrocodone—within the ambit of the indictment. Although heroin is an opiate, not all opiates are heroin. Therefore, when the original indictment was amended to include hydrocodone, a new substance was effectively alleged in the indictment. The court found its holding consistent with the proposition that a critical purpose of the indictment is to enable the accused to prepare for trial. Here, the State moved to amend on the morning of trial. Until then, the defendant had justifiably relied on the original indictment in preparing his defense. In fact this concern was expressed by defense counsel in his objection to the motion to amend, specifically arguing that the defendant had no knowledge that the hydrocodone would be included in the trafficking amount. Additionally, the State sought to amend the indictment only after the defendant informed the trial court of his intention to admit possessing some, but not all, of the heroin. The logical inference of the sequence is that upon learning of the defendant’s trial strategy on the morning of trial, the State sought to thwart that strategy by broadening the scope of the indictment. The court stated: “In essence, the State was permitted to change the rules of the game just as the players were taking the field.”